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-rw-r--r--sysdeps/ieee754/sqrt.c120
1 files changed, 0 insertions, 120 deletions
diff --git a/sysdeps/ieee754/sqrt.c b/sysdeps/ieee754/sqrt.c
deleted file mode 100644
index 7e350e0d91..0000000000
--- a/sysdeps/ieee754/sqrt.c
+++ /dev/null
@@ -1,120 +0,0 @@
-/*
- * Copyright (c) 1985 Regents of the University of California.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms are permitted provided
- * that: (1) source distributions retain this entire copyright notice and
- * comment, and (2) distributions including binaries display the following
- * acknowledgement: ``This product includes software developed by the
- * University of California, Berkeley and its contributors'' in the
- * documentation or other materials provided with the distribution and in
- * all advertising materials mentioning features or use of this software.
- * Neither the name of the University nor the names of its contributors may
- * be used to endorse or promote products derived from this software without
- * specific prior written permission.
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
- */
-
-#include <ansidecl.h>
-#include <errno.h>
-#include <math.h>
-
-/* Return the square root of X. */
-double
-DEFUN (sqrt, (x), double x)
-{
- double q, s, b, r, t;
- CONST double zero = 0.0;
- int m, n, i;
-
- /* sqrt (NaN) is NaN; sqrt (+-0) is +-0. */
- if (__isnan (x) || x == zero)
- return x;
-
- if (x < zero)
- return zero / zero;
-
- /* sqrt (Inf) is Inf. */
- if (__isinf (x))
- return x;
-
- /* Scale X to [1,4). */
- n = __logb (x);
- x = __scalb (x, -n);
- m = __logb (x);
- if (m != 0)
- /* Subnormal number. */
- x = __scalb (x, -m);
-
- m += n;
- n = m / 2;
-
- if ((n + n) != m)
- {
- x *= 2;
- --m;
- n = m / 2;
- }
-
- /* Generate sqrt (X) bit by bit (accumulating in Q). */
- q = 1.0;
- s = 4.0;
- x -= 1.0;
- r = 1;
- for (i = 1; i <= 51; i++)
- {
- t = s + 1;
- x *= 4;
- r /= 2;
- if (t <= x)
- {
- s = t + t + 2, x -= t;
- q += r;
- }
- else
- s *= 2;
- }
-
- /* Generate the last bit and determine the final rounding. */
- r /= 2;
- x *= 4;
- if (x == zero)
- goto end;
- (void) (100 + r); /* Trigger inexact flag. */
- if (s < x)
- {
- q += r;
- x -= s;
- s += 2;
- s *= 2;
- x *= 4;
- t = (x - s) - 5;
- b = 1.0 + 3 * r / 4;
- if (b == 1.0)
- goto end; /* B == 1: Round to zero. */
- b = 1.0 + r / 4;
- if (b > 1.0)
- t = 1; /* B > 1: Round to +Inf. */
- if (t >= 0)
- q += r;
- } /* Else round to nearest. */
- else
- {
- s *= 2;
- x *= 4;
- t = (x - s) - 1;
- b = 1.0 + 3 * r / 4;
- if (b == 1.0)
- goto end;
- b = 1.0 + r / 4;
- if (b > 1.0)
- t = 1;
- if (t >= 0)
- q += r;
- }
-
-end:
- return __scalb (q, n);
-}